Synthesis and field emission properties of silicon carbide nanobelts with a median ridge

beta-Silicon carbide (beta-SiC) nanobelts with a median ridge have been synthesized for the first time via a template/catalyst-free chemical vapor reaction (CVR) method. The characterization results show that the beta-SiC nanobelts with widths of 1.5 mu m and thickness of about 10-20 nm consist of nanowires with rough surfaces in diameters of 100 nm (median ridge) and two symmetrical lateral flakes with uniform width. A reasonable two-step Vapor-Solid (TSVS) growth mechanism is proposed to explain the formation of the nanobelts on the basis of crystal growth theory. Using the beta-SiC nanobelts as the cathode, the result of field-emission measurements shows that the turn-on field and threshold field of the beta-SiC nanobelts are about 3.2 V mu m(-1) and 5.7 V mu m(-1), respectively. These features make the beta-SiC nanobelts a promising candidate for field emission displays. The beta-SiC nanobelts obtained in this work enrich the family of silicon carbides nanostructures; moreover, the method and growth mechanism could be an effective clue and example for the synthesis of belt-like nanostructures of other materials.